American disapproval of President Barack Obama’s foreign policy has shot up recently, especially as the situation in Iraq worsens. Democrats and Republicans are increasingly alike in their unhappiness, with former Obama administration officials such as Anne-Marie Slaughter bitterly denouncing the White House as “blind” and Hillary Clinton “getting distance” from the president’s decisions.

But here is a question for all those deriding Obama’s failures: What if the nihilists of the Islamic State of Iraq and Syria were armed with chemical weapons?

Lost in last month’s explosive news from Iraq was the United Nations announcement that “Syria has destroyed all declared production, mixing and filling equipment and munitions, as well as many buildings associated with its declared chemical weapons program.” The June 30 removal deadline set by the Security Council last September has, against all odds and most predictions, been met — a success attributable to an aggressive multinational program administered jointly by Moscow and Washington — even through Russia’s provocations in Ukraine.

All of Bashar Assad’s “declared” chemical arsenal is gone. Even if the Syrian dictator has somehow kept a small lethal hoard, it is necessarily remote and locked. As one expert put it, “The near elimination of one of the two largest operational chemical weapons arsenals in the world, in the midst of the chaos of a civil war no less, is remarkable.”

Less than a year ago, sarin gas was loosed on civilians in Syria, probably by Assad, an action that horrified the world and prompted Obama’s September initiatives. Now, Assad is party to the U.N. Chemical Weapons Convention. If, instead of joining Russia to forge the international alliance that made this triumph possible, Obama had fired off a barrage of cruise missiles, almost certainly escalating the savage violence in Syria, who believes the horror of chemical warfare would have been contained?

And who believes the fanatics of ISIS would not have taken advantage of that deadly circumstance? Last month, those jihadists, storming through Iraq, took control of an abandoned chemical weapons site that had belonged to Saddam Hussein. Fortunately, it was “a wasteland full of destroyed chemical munitions, razed structures and unusable war-ravaged facilities,” as a CIA assessment put it. Whatever is left of Hussein’s gravely degraded material threatens the militants moving it more than anyone they could target, but the seizure suggests what the ISIS dream strategy includes.

If, by contrast to the Hussein remnant, Syria’s supremely usable chemical weapons had been rendered vulnerable to ready theft by escalated chaos during the past year, much less if they had been deployed and unleashed instead of removed and destroyed, ISIS could be assumed by now to have turned Baghdad into a poisoned charnel house.

In the larger region, the elimination of Syria’s chemical arsenal itself advances the entire anti-proliferation movement that Obama long ago put at the center of his purpose. Any further unleashing of chemical weapons, whether by Assad or ISIS, would have significantly increased regional pressures for the acquisition of weapons of mass destruction of all kinds, undercutting especially the delicate and ongoing process of constraining Iran’s nuclear ambitions.

That negotiations with Iran, which may come to climax this month, have continued through this year’s bedlam is another ignored signal of Obama foreign policy prowess. Steps are being taken back from the WMD abyss.

Political leaders rarely get credit for the disasters they avert. But it is a failure of the imagination not to have in mind, as one evaluates Obama’s performance, that the field on which he operates is strewn with mines — and that armed intervention is highly unlikely to make things better instead of worse. Obama is consciously attempting to change a failed international power dynamic, moving from a century of military diktat to a strategy, as he called it at West Point, of “empowering partners” to advance American interests, human rights and the resolution of conflict.

But for such leadership to actually bring into being structures and networks capable of reshaping international politics, the U.S. citizenry has a role to play — liberals as well as conservatives. We must surrender our habit of magical thinking about American power, understanding that a new world is struggling to be born. Obama is speaking of that world. The more distressed its dangers make us, the more we should give him the benefit of our uncertainty.